By Brett Hartl
Hikers exploring the canyons and bluffs of Laguna Coast Wilderness Park may not know it, but they are in the midst of the incredible comeback of one of California’s most endangered species.
Pacific pocket mice recently released into the San Joaquin Hills by the San Diego Zoo have begun breeding on their own. It’s a milestone for this tiny animal once thought extinct and a testament to the power of the Endangered Species Act.
As someone who has lived and worked in the San Diego area on the recovery of the least Bell’s vireo and California gnatcatcher, this is wonderful news for these cute little mice.
The tiny Pacific pocket mouse — the smallest mouse in the country — plays an important role in spreading native plant seeds and keeping grassland habitats healthy. Although these mice were once found from Los Angeles to the Mexican border, they were nearly lost forever. Habitat loss from development decimated the population to the point that it was believed to be extinct.
Luckily a small population was “rediscovered” in 1993. They quickly received emergency endangered species protection from the U.S. Fish and Wildlife Service, and a captive breeding program was initiated shortly after.
The designation as an endangered species kicked off efforts by federal and state wildlife agencies working alongside San Diego Zoo researchers to restore their habitat and reintroduce them from the wild. Today there are three populations and the first confirmed breeding in the wild in decades. A pretty good start for this little mouse.
The success that the pocket mouse is experiencing is not the exception but the rule for animals protected under the Endangered Species Act. This bedrock environmental law has saved more than 99 percent of species under its protection and put hundreds more on the road to recovery.
The least Bell’s vireo, a species I worked on as a field biologist, is another success story. Once common in riverside woodlands in Southern California and the Central Valley, habitat loss from development reduced the bird to just 300 pairs by 1986.
Following protection under the Endangered Species Act that year, sensible restrictions on development in river bottom areas and restoration of cottonwood and willow woodlands, the vireo population increased dramatically to 2,500 pairs in 2004. The vireo may soon be declared to be recovered and removed from the endangered species list.
The California brown pelican is another example. The pelican population in California had fallen to 727 nesting pairs in 1970 when it was listed. Thanks to the Endangered Species Act and the banning of DDT, the population rose to 6,000 nesting pairs in 2004. Channel Island foxes, blue whales and southern sea otters have all also bounced back thanks to these protections.
None of these successes would have been possible without the Endangered Species Act. However, if congressional Republicans have anything to say about it, that good work would be stopped in its tracks.
Since the new Congress took over in January, anti-wildlife politicians have launched 47 legislative attacks on the Endangered Species Act — despite the act’s immense success and broad public support for this critical environmental law. These attacks are mainly at the behest of the fossil fuel industry and other special interests that oppose any restrictions on their activities.
But the success of the pocket mouse and many other California species shows that reasonable development can occur as long as we continue to make space for our most imperiled wildlife, even in some of the most populated parts of the country.
Brett Hartl is government affairs director for the Tucson-based Center for Biological Diversity.
